In many IC applications, some means for monitoring a voltage state of certain elements on the IC are needed. For example, when an input voltage supply to one or more elements on the IC falls below a certain voltage threshold, a “reset” signal might be generated to reset the IC in order to avoid damage to the IC.
A voltage detector circuit implementing a low voltage detection function may be used to monitor the voltage state of the elements on the IC. The voltage detector circuit may include a voltage divider coupled to a field effect transistor (FET). A scaled input voltage taken across the voltage divider may be supplied to the gate input of the FET. If an input voltage supply is high, the FET will be turned on, in which case the voltage detector circuit does not issue a reset signal. On the other hand, if the input voltage supply drops below a certain voltage threshold, the FET will be turned off, and the voltage detector circuit generates a reset signal to reset the IC. The above-described voltage detector circuit incurs high power consumption since the resistive voltage divider constantly drains current from the input voltage supply. In addition, since the voltage detector circuit requires a certain voltage threshold to turn on the FET, the voltage threshold required to trigger the reset signal may not be low enough. As a result, unnecessary reset signal may occur at the output of the voltage detector circuit.